Inhibitory effects of Nelumbo nucifera leaves on rat lens aldose reductase, advanced glycation endproducts formation, and oxidative stress.
The preventive and therapeutic potency against oxidative stress and diabetic complications of Nelumbo nucifera were evaluated via the 1,1-diphenyl-2-picrylhydrazyl (DPPH), Trolox equivalent antioxidant capacity (TEAC), and total reactive oxygen species (ROS) assays, as well as the rat lens aldose reductase (RLAR) and advanced glycation endproducts (AGE) assays. The leaf extract of N. nucifera exerted potent antioxidant effects as well as marked inhibitory effects for RLAR and AGE formation, corresponding to high values for total phenolic content (TPC) and total flavonoid content (TFC). Among several solvent fractions, the EtOAc and n-BuOH fractions, having prominent TPC and TFC values, showed significant antioxidant effects in the DPPH and TEAC assays. Moreover, the EtOAc fraction exhibited superior inhibitory effects in the total ROS, RLAR, and AGE assays, with IC(50) values of 9.4, 2.4, and 28.2microg/ml, respectively. Also, the HPLC profiles of the active EtOAc fraction indicated that quercetin 3-O-beta-d-glucopyranoside (Qc-3-Glc) and Qc 3-O-beta-d-glucuronopyranoside (Qc-3-Gln) were two of its major components, as well as Qc 3-O-beta-d-galactopyranoside (Qc-3-Gal) as a minor compound. Therefore, the results suggest that two key antioxidant flavonoids, Qc-3-Glc and Qc-3-Gln, may play important roles in the antioxidant and RLAR inhibitory effects of N. nucifera leaves. Also, the leaves, and the flavonoids contained within them, would clearly have potential uses in the development of therapeutic or preventive agents for diabetic complications and oxidative stress-related diseases.
Jung
Hyun Ah
HA
Division of Food Science and Biotechnology, Pukyong National University, Busan 608-737, South Korea.
Jung
Yu Jung
YJ
Yoon
Na Young
NY
Jeong
Da Mi
DM
Bae
Hyun Ju
HJ
Kim
Dong-Wook
DW
Na
Dong Hee
DH
Choi
Jae Sue
JS
D000449:Aldehyde Reductase / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001713:Biphenyl Compounds; D002839:Chromans / Q000494:pharmacology; D003930:Diabetic Retinopathy / Q000473:pathology / Q000517:prevention & control; D005419:Flavonoids / Q000737:chemistry / Q000494:pharmacology; D016166:Free Radical Scavengers / Q000378:metabolism; D017127:Glycation End Products, Advanced; D007908:Lens, Crystalline / Q000187:drug effects / Q000201:enzymology*; D008297:Male; D000432:Methanol; D031653:Nelumbo / Q000737:chemistry*; D018384:Oxidative Stress / Q000187:drug effects*; D010636:Phenols / Q000737:chemistry / Q000494:pharmacology; D010851:Picrates; D018515:Plant Leaves / Q000737:chemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism; D012997:Solvents
D000975:Antioxidants; D001713:Biphenyl Compounds; D002839:Chromans; D005419:Flavonoids; D016166:Free Radical Scavengers; D017127:Glycation End Products, Advanced; D010636:Phenols; D010851:Picrates; D017382:Reactive Oxygen Species; D012997:Solvents; C004931:1,1-diphenyl-2-picrylhydrazyl; D000449:Aldehyde Reductase; C010643:6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid; D000432:Methanol